In response to a Chinese initiative, an International Workshop on the principles of environmental mutagenesis, carcinogenesis and teratogenesis is planned to take place May 1983 in Shanghai, the People's Republic of China, under the joint sponsorhip of the Shanghai Association for Science and Technology and the International Union of Environmental Mutagen Societies. The aim is to review the current knowledge on the scientific basis of environmental toxicology and to assess and compare the methodologies dealing with human risk problems in China and other countries. A six day program will consist of 40 lectures given by leading scientists, 8 of them from Western Europe, 5 from Japan and 12 from the U.S. The formal presentations will be published in the U.S. About 200 scientists from all over China and about 20 scientists from countries in Southeast Asia representing academic, research and industrial institutions are expected to attend. Poster sessions have been planned for the Chinese and other Southeast Asian participants to present their work and English summaries of these contributions will be included in the volume. The cost of the Workshop will be borne mainly by the Chinese organizers. This application is for a bloc grant to support the U.S. participants for their intenational travel expenses and living expenses during this Workshop in China. Support is requested for secretarial and material support during the organization of the Workshop and also the publishing cost of the proceedings. The European and Japanese participants will seek support for travel and living expenses from their own countries.